Dong Ik Cha

Percutaneous Radiofrequency Ablation of Hepatocellular Carcinoma: Fusion Imaging Guidance for Management of Lesions With Poor Conspicuity at Conventional Sonography

OBJECTIVE The purpose of this study was to determine whether fusion imaging-guided percutaneous radiofrequency ablation (RFA) is effective in the management of hepatocellular carcinoma (HCC) that has poor conspicuity at conventional sonography. SUBJECTS AND METHODS Percutaneous RFA of HCC with poor conspicuity was performed under fusion imaging guidance. The time needed for image fusion between the ultrasound and CT or MR images was recorded. The quality of image fusion and the degree of operator confidence in identifying the index tumor were graded on 4-point scales. Technical success and procedure-related complications were evaluated with liver CT immediately after RFA. RESULTS Thirty patients with HCC (1.0 ± 0.3 cm) were enrolled. Twenty-seven of the 30 lesions detected at planning ultrasound were identified with fusion imaging. Of the 30 HCC candidate lesions detected with ultrasound, five were found to be pseudolesions close to the index tumor. The time needed for image fusion for the 27 lesions was 3.7 ± 2.1 minutes (range, 1.3-9.0 minutes). The quality of image fusion was graded 3.4 ± 0.6, and the degree of operator confidence in identifying the 30 HCCs, 3.3 ± 0.9. The technical success rate was 90% (27/30) in intention-to-treat analysis and 100% in analysis of actually treated lesions. There were no major RFA-related complications. CONCLUSION Fusion imaging-guided percutaneous RFA is effective in the management of HCC that has poor ultrasound conspicuity.

Fusion Imaging–Guided Radiofrequency Ablation for Hepatocellular Carcinomas Not Visible on Conventional Ultrasound

OBJECTIVE The objective of our study was to assess whether fusion imaging of conventional ultrasound and liver CT or MR images can improve the conspicuity of lesions and feasibility of percutaneous radiofrequency ablation (RFA) for the treatment of hepatocellular carcinomas (HCCs) not visible on ultrasound. Whether peritumoral anatomic landmarks can be used for the placement of an electrode in HCCs not visible on ultrasound even after image fusion was also evaluated. MATERIALS AND METHODS Planning ultrasound for percutaneous RFA was performed using conventional ultrasound first and then using fusion imaging later during the same session. The visibility of HCCs and feasibility of RFA on conventional ultrasound and on fusion imaging were assessed. We evaluated how many HCCs initially not visible on conventional ultrasound could be visualized and ablated after applying the fusion imaging technique. One hundred twenty HCCs not visible on conventional ultrasound in 96 patients were included. RESULTS When fusion imaging was applied, 38 of the 120 (31.7%) HCCs that were initially not visible could be seen and RFA was feasible. Among the remaining 82 HCCs still not visible after image fusion, 26 (31.7%) were ablated under the guidance of fusion imaging the technique based on peritumoral anatomic landmarks. Overall, 64 of 120 (53.3%) HCCs (59.4%, 57 of 96 patients) not visible on conventional ultrasound could be ablated under the guidance of the fusion imaging technique. CONCLUSION Fusion imaging can improve the conspicuity of HCCs and the feasibility of percutaneous RFA of HCCs not visible on conventional ultrasound. Peritumoral anatomic landmarks can be used for electrode placement in HCCs that are still not visible even after image fusion.

Planning US for percutaneous radiofrequency ablation of small hepatocellular carcinomas (1-3 cm): value of fusion imaging with conventional US and CT/MR images.

PURPOSE To assess whether fusion of conventional ultrasonography (US) with liver computed tomography/magnetic resonance images for planning US for percutaneous radiofrequency (RF) ablation can reduce false-positive detection and enhance lesion detectability of small hepatocellular carcinomas (HCCs) on conventional US. MATERIALS AND METHODS This retrospective study was approved by the institutional review board, and informed consent was waived. A total of 137 patients with single HCCs (mean ± standard deviation, 1.7 ± 0.6 cm; range, 1.1-3.0 cm) were included. Planning US was performed by two radiologists by using conventional US first and fusion imaging later in the same session. The false-positive detection rate of conventional US was assessed with the results of fusion imaging used as a reference standard. True-positive detection rates on conventional US and fusion imaging were compared by McNemar test. Initially undetectable HCCs on conventional US that became detectable after image fusion were also assessed. RESULTS The false-positive detection rate of conventional US was 7.7% (nine of 117). Overall true-positive detection rates on conventional US and fusion imaging were 78.8% (108 of 137) and 90.5% (124 of 137), respectively (P = .0002); the rates were significantly different between conventional US and fusion imaging for HCCs smaller than 2.0 cm, but not for HCCs 2.0 cm or larger. Of 20 initially undetectable HCCs on conventional US, nine (45.0%) became detectable after image fusion. CONCLUSIONS Fusion imaging for planning US for percutaneous RF ablation can reduce false-positive detection and enhance lesion detectability of small HCCs on conventional US.

Therapeutic Efficacy and Safety of Percutaneous Ethanol Injection with or without Combined Radiofrequency Ablation for Hepatocellular Carcinomas in High Risk Locations

Objective To evaluate the therapeutic efficacy and safety of percutaneous ethanol injection (PEI) alone and combined with radiofrequency ablation (RFA) for hepatocellular carcinomas (HCCs) in high risk locations. Materials and Methods We performed PEI for HCCs in RFA-high risk locations, either alone or in combination with RFA. There were 20 HCCs (1.7 ± 0.9 cm) in 20 patients (PEI group: n = 12; PEI + RFA group: n = 8). We evaluated technical success, local tumor progression and complications in both groups. Results Technical success was achieved in all HCCs in both groups. During follow-up, local tumor progression was found in 41.7% (5/12) in the PEI group, whereas 12.5% (1/8) for the PEI + RFA group (p = 0.32). Bile duct dilatation was the most common complication, especially when the tumors were in periportal locations; 55% (5/9) in the PEI group and 50% (2/4) in the PEI + RFA group (p = 1.00). One patient in the PEI group developed severe biliary stricture and upstream dilatation that resulted in atrophy of the left hepatic lobe. One patient treated with PEI + RFA developed cholangitis and an abscess. Conclusion Combined PEI and RFA treatment has a tendency to be more effective than PEI alone for managing HCCs in high risk locations, although the difference is not statistically significant. Even though PEI is generally accepted as a safe procedure, it may cause major biliary complications for managing HCCs adjacent to the portal vein.

Mistargeting after Fusion Imaging–Guided Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas

PURPOSE To evaluate the incidence and causes of mistargeting after fusion imaging-guided percutaneous radiofrequency (RF) ablation of hepatocellular carcinomas (HCCs). MATERIALS AND METHODS Between September 2011 and March 2013, 955 HCCs in 732 patients were treated with percutaneous RF ablation. Among them, ablation of 551 HCCs was accomplished under fusion imaging guidance, and seven mistargetings were noted in seven patients (male-to-female ratio = 6:1; mean age, 60.1 y; range, 47-73 y). The incidence of mistargeting and the cause of liver disease in the patients with mistargeting were evaluated. The causes of mistargeting were assessed according to the following classification: small size of HCC, subcapsular location, subphrenic location, confusion with pseudolesions, poor conspicuity of HCC, poor sonographic window, and poor electrode path. RESULTS The incidence of mistargeting after fusion imaging-guided RF ablation was 1.3% (7 of 551). All patients with mistargeting were hepatitis B virus carriers. The most common cause of mistargeting was the small size of HCC (100%; 7 of 7), followed by confusion with surrounding pseudolesions (85.7%; 6 of 7), subcapsular (71.4%; 5 of 7) and subphrenic locations (71.4%; 5 of 7), poor conspicuity of the HCC (71.4%; 6 of 7), poor sonographic window (28.6%; 2 of 7), and poor electrode path (28.6%; 2 of 7). CONCLUSIONS The incidence of mistargeting after fusion imaging-guided RF ablation was 1.3%. The most common cause of mistargeting was the small size of HCC, followed by confusion with surrounding pseudolesions, subcapsular and subphrenic locations, and poor conspicuity of the HCC.

Assessing patients with hepatocellular carcinoma meeting the Milan criteria: Is liver 3 tesla MR with gadoxetic acid necessary in addition to liver CT?

To determine the added value of 3 Tesla liver MR in patients with hepatocellular carcinoma (HCC) within the liver computed tomography (CT) ‐based Milan criteria.

Pretreatment Evaluation with Contrast-Enhanced Ultrasonography for Percutaneous Radiofrequency Ablation of Hepatocellular Carcinomas with Poor Conspicuity on Conventional Ultrasonography

OBJECTIVE To determine whether pretreatment evaluation with contrast-enhanced ultrasonography (CEUS) is effective for percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) with poor conspicuity on conventional ultrasonography (US). MATERIALS AND METHODS This retrospective study was approved by the institutional review board and informed consent was waived. From June 2008 to July 2011, 82 patients having HCCs (1.2 ± 0.4 cm) with poor conspicuity on planning US for RFA were evaluated with CEUS prior to percutaneous RFA. We analyzed our database, radiologic reports, and US images in order to determine whether the location of HCC candidates on planning US coincide with that on CEUS. To avoid incomplete ablation, percutaneous RFA was performed only when HCC nodules were identified on CEUS. The rate of technical success was assessed. The cumulative rate of local tumor progression was estimated with the use of the Kaplan-Meier method (mean follow-up: 24.0 ± 13.0 months). RESULTS Among 82 patients, 73 (89%) HCCs were identified on CEUS, whereas 9 (11%) were not. Of 73 identifiable HCCs on CEUS, the location of HCC on planning US corresponded with that on CEUS in 64 (87.7%), whereas the location did not correspond in 9 (12.3%) HCCs. Technical success was achieved for all 73 identifiable HCCs on CEUS in a single (n = 72) or two (n = 1) RFA sessions. Cumulative rates of local tumor progression were estimated as 1.9% and 15.4% at 1 and 3 years, respectively. CONCLUSION Pretreatment evaluation with CEUS is effective for percutaneous RFA of HCCs with poor conspicuity on conventional US.

Radiofrequency Ablation Combined with Chemoembolization for Intermediate-Sized (3-5 cm) Hepatocellular Carcinomas Under Dual Guidance of Biplane Fluoroscopy and Ultrasonography

Objective To assess the technical feasibility and local efficacy of percutaneous radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) for an intermediate-sized (3-5 cm in diameter) hepatocellular carcinoma (HCC) under the dual guidance of biplane fluoroscopy and ultrasonography (US). Materials and Methods Patients with intermediate-sized HCCs were treated with percutaneous RFA combined with TACE. RFA was performed under the dual guidance of biplane fluoroscopy and US within 14 days after TACE. We evaluated the rate of major complications on immediate post-RFA CT images. Primary technique effectiveness rate was determined on one month follow-up CT images. The cumulative rate of local tumor progression was estimated with the use of Kaplan-Meier method. Results Twenty-one consecutive patients with 21 HCCs (mean size: 3.6 cm; range: 3-4.5 cm) were included. After TACE (mean: 6.7 d; range: 1-14 d), 20 (95.2%) of 21 HCCs were visible on fluoroscopy and were ablated under dual guidance of biplane fluoroscopy and US. The other HCC that was poorly visible by fluoroscopy was ablated under US guidance alone. Major complications were observed in only one patient (pneumothorax). Primary technique effectiveness was achieved for all 21 HCCs in a single RFA session. Cumulative rates of local tumor progression were estimated as 9.5% and 19.0% at one and three years, respectively. Conclusion RFA combined with TACE under dual guidance of biplane fluoroscopy and US is technically feasible and effective for intermediate-sized HCC treatment.

Recurrent Hepatocellular Carcinoma After Transcatheter Arterial Chemoembolization Planning Sonography for Radio Frequency Ablation

The purposes of this study were to evaluate the sonographic findings of recurrent hepatocellular carcinoma after transcatheter arterial chemoembolization and to determine how often the lesion conspicuity of the recurrent hepatocellular carcinoma makes it suitable for percutaneous sonographically guided radio frequency ablation.

Radiofrequency Ablation for Viable Hepatocellular Carcinoma around Retained Iodized Oil after Transcatheter Arterial Chemoembolization: Usefulness of Biplane Fluoroscopy Plus Ultrasound Guidance

Objective To assess the technical feasibility and local efficacy of biplane fluoroscopy plus US-guided percutaneous radiofrequency ablation (RFA) for viable hepatocellular carcinoma (HCC) around retained iodized oil after transcatheter arterial chemoembolization (TACE). Materials and Methods Our prospective study was approved by our institutional review board and informed consent was obtained from all participating patients. For patients with viable HCC around retained iodized oil after TACE, biplane fluoroscopy plus US-guided RFA was performed. We evaluated the rate of technical success and major complications on a post-RFA CT examination and local tumor progression with a follow-up CT. Results Among 40 consecutive patients, 19 were excluded due to one of the following reasons: poorly visible HCC on fluoroscopy (n = 13), high risk location (n = 2), RFA performed under monoplane fluoroscopy and US guidance (n = 2), and poorly identifiable new HCCs on US (n = 2). The remaining 21 patients with 21 viable HCCs were included. The size of total tumors ranged from 1.4 to 5.0 cm (mean: 3.2 cm) in the longest diameter. Technical success was achieved for all 21 HCCs, and major complications were observed in none of the patients. During the follow-up period (mean, 20.3 months; range, 6.5-29.9 months), local tumor progression was found in two patients (2/21, 9.5%). Distant intrahepatic metastasis developed in 76.2% (16/21) of patients. Conclusion When retained iodized oil around the tumor after TACE hampers the targeting of the viable tumor for RFA, biplane fluoroscopy plus US-guided RFA may be performed owing to its technical feasibility and effective treatment for viable HCCs.